WASHINGTON (AP) — House Democrats are demanding the release of a transcript from a new FBI witness that they say contradicts Republicans' claims in the expanding congressional inquiry into President Joe Biden's son, Hunter Biden.

Rep. Jamie Raskin, the top Democrat on House Oversight Committee, sent a letter Friday to Rep. James Comer, the Republican chair of the committee, asking him to produce the transcribed interview this month with an FBI agent who worked on the investigation into the younger Biden's taxes and foreign business dealings. The witness was interviewed on July 17.

"This failure to release a transcript is the latest in your troubling pattern of concealing key evidence in order to advance a false and distorted narrative about your 'investigation of Joe Biden' that has not only failed to develop any evidence of wrongdoing by President Biden but has, in fact, uncovered substantial evidence to the contrary," Raskin wrote in the letter, which was obtained by The Associated Press.

The Maryland lawmaker claimed the closed-door interview with the unidentified agent conducted by committee staff "directly undermined" testimony released by Republicans last month from two IRS whistleblowers who allege that the Justice Department interfered with their yearslong investigation into Hunter Biden.

Republicans said the transcript will be released but is not yet ready. "The transcript is going through the normal review process where the witness reviews it and makes any corrections needed," the GOP majority tweeted Thursday night. "Once that process has been completed, we will release it."

House rules allow only the majority party to release transcribed interviews from a committee investigation, meaning minority Democrats have no direct power over the matter.

Raskin says in the letter that it is unusual for the release of a transcript to take this long. However, it is not unusual for committee staff to handle whistleblowers cautiously and keep sensitive information tightly held.

The letter from Raskin comes days after Hunter Biden's plea deal in a criminal case unraveled during a court hearing. A federal judge in the case raised concerns about the terms of the agreement. Republicans like Comer claimed vindication, having slammed the agreement as a "sweetheart deal."

"The judge did the obvious thing, they put a pause on the plea deal, so I think that was progress," Comer said Wednesday. "I think it adds credibility to what we're doing."

The president's youngest son was charged last month with two misdemeanor crimes of failure to pay more than $100,000 in taxes on over $1.5 million in income in both 2017 and 2018. He had been expected to plead guilty Wednesday after he made an agreement with prosecutors, who wanted two years of probation.

Prosecutors said Wednesday that Hunter Biden remains under active investigation, but would not reveal details.